In a rolling mill for the production of metal strips, for example a rolling mill for the production of steel strip, the metal strips are coiled up in coiling facilities at the end of the production process. The coiling facilities have so-called drive facilities, also called drivers. In these, the metal strip is stretched between a pair of rollers, the metal strip's direction is reversed and then driven to wind it up onto the coil. The typical use of drivers is in rolling lines, where the drivers are arranged before hot-rolled strip coilers. During the process of coiling up, their functions include among others that of adjusting the front tension ahead of the coiling unit by means of a pair of rollers, also called drive rollers, namely the drive roller and the reverse drive roller. In this arrangement, the drive roller is located above the reverse drive roller. The drive roller is generally constructed as a hollow roller, and the reverse drive roller generally as a solid roller.
Conventional rollers are often used for drive rollers, they are hollow right through—and are called hollow rollers. The disadvantage with hollow rollers is that they must be provided with welded axle shafts right through them. Due to the high mechanical loading placed on them, these axle shafts are mostly manufactured from special forged steels, which require special manufacturing and welding machines because of their dimensions. Such axle shafts are thus difficult to manufacture, which makes their production expensive and time-consuming and results in long delivery lead-times. Long delivery lead-times, for example up to 6 months in the case of drive rollers for a rolling mill driver, are a factor which leads to increased costs for stockholding. In addition, greater financial resources are tied up so that the production of the rolling mill does not suffer detrimental effects from the problems of regular replacement of worn-out drive rollers and reverse drive rollers.
The drive rollers wear out parts which, because of the need to replace them regularly, requires the operator of a rolling mill to constantly have an adequate number in store.
In a rolling mill, drive rollers are used during rolling for the production of metal strips, for example steel strips or aluminum strips.
Since rolling lines are subject to a constant process of development, coiling facilities are continuously being extended or modified. A consequence of this is that there are generally drivers with various types of construction installed in a rolling line. The dimensions of the stub axle shafts are adapted for the relevant coupling dimensions or, as applicable, to the relevant distance between the bearings of the drive rollers or the reverse drive rollers, and hence drive rollers with different dimensions are used. Another disadvantage of drive rollers in accordance with the prior art is that in the drivers for different rolling lines use is often made of drive rollers and reverse drive rollers of different lengths. The dimensions of the drive rollers and the reverse drive rollers are determined according to the maximum width of strip produced on the individual rolling lines. This means that it is often impossible to exchange drive rollers and reverse drive rollers for one rolling line by the drive rollers and reverse drive rollers for other rolling lines.
The reasons just described have the consequence that it is costly to hold an adequate reserve stock of drive rollers and reverse drive rollers, and doing so ties up substantial financial resources.